The present invention relates to a novel and useful fluid damper.
Dampers are used to control fluid such as air in edifices and other facilities. Airflow control is acutely necessary in clean structures, often requiring dampers in the ceiling and floor.
In the past, dampers have followed two basic designs a xe2x80x9cbutterflyxe2x80x9d and a xe2x80x9csplit butterflyxe2x80x9d arrangement. Both designs utilize a central axis in which blades are extended outwardly and lies perpendicular to the flow of air. Unfortunately, these prior designs suffer from deficiencies in that positioning of the blades or xe2x80x9csetxe2x80x9d is often lost due to the flow of air against the blades. Thus, the control of airflow via the prior art designs is difficult to achieve. In addition, noise is easily generated by the xe2x80x9cbutterflyxe2x80x9d and xe2x80x9csplit butterflyxe2x80x9d designs. These problems are exacerbated by flow rates of air required by clean room structures.
Prior structures have been proposed to control the flow of air in a ventilation conduit. For example, U.S. Pat. Nos. 916,484 and Des. 347,471 show ventilators and dampers of conventional configuration.
U.S. Pat. Nos. 3,070,346, 3,095,178, and 4,817,508 describe dampers having veins which are rotatable or pivotal within a conduit and include reinforcements to aid in their stability.
U.S. Pat. No. 4,188,862 describes a register assembly in which louvers are rotated about a central hub to control airflow.
U.S. Pat. No. 4,094,492 shows a variable xe2x80x9cirisxe2x80x9d orifice flow control in which a plurality of blades or flanges open and close in the same manner as a camera shutter.
U.S. Pat. No. 3,068,891 illustrates a flow regulator in which a series of plates are rotated about a central shaft and are cantilevered from the same to control airflow.
U.S. Pat. No. 6,010,113 teaches a damper with fanning blades which are rotatably attached to a central hub. The peripheral ends of the blades fit into a groove to guide the same in a rotary manner.
U.S. Pat. No. 2,235,731 shows a damper in which angularly disposed damper elements arrange to fit on fixed elements to open and close an opening as a damper element is moved through arcuate slots.
A damper which exhibits precise control in high fluid flow conditions would be a notable advance in the mechanical arts.
In accordance with the present invention a novel and useful damper is herein provided.
The damper of the present invention utilizes a frame having a base which may be constructed in an endless configuration such as one that is circular, annular, rectangular, and the like. The base includes a wall portion which extends outwardly from the base and includes an end which is also an endless member. The frame defines an aperture or opening generally used for the passage of air in a fluid or air circulation system such as a conduit. The frame may be fastened to a conduit or filter system by conventional means.
A stepped edge portion is located at the end of the wall portion and is positioned to at least partially circumvent the aperture. The stepped edge portion may be constructed separately and attached to the wall portion, or formed integrally therewith. The frame, and its components described above, may be manufactured from any rigid or semi-rigid material such as metal, ceramics, plastics, and the like.
A plurality of flanges or blades are also employed in the present invention. At least a first and a second flange are used and are positioned in overlying relationship to one another. Thus, the first flange is movable relative to the second flange in a sliding relationship. An appropriate number of flanges are employed to close or occlude the aperture formed by the frame when the flange is fanned out or spread across the aperture in such sliding arrangement. The flanges are supported by a central hub which may be turned using any mechanical means, and may be locally or remotely operated. Of course, the central hub may be turned or rotated using automatic controls known in the art.
Means is also provided in the present invention for moving the first and second flanges relative to one another in an overriding relationship. Such means may be manual or take the form of a motor known in the art. The motor may transmit such rotary motion via the shaft and a gearing arrangement of conventional configuration. The plurality of flanges ride on the step edge portion of the frame during overriding movement relative to one another. The stepped edge portion serves to guide and to uniformly spread the plurality of flanges across the aperture during the process of closing or occluding of the aperture. Such movement may be accomplished by using a pair of wheels, a first wheel pivotally linked to the first flange and a second wheel rotatable relative to a bracket supported by the frame. The second wheel may serve as an extension of the shaft that is movable manually by a motor, remotely or locally. The wheels may take the form of gears to more positively control the movement of the first flange relative to the aperture of the frame.
Linking means is also provided for permitting the first flange to engage the second flange and to pull the same in a rotational manner about the central pivot. Such linking means may include a tab formed on the first flange and a slot constructed on the second flange such that the tab locates within the slot and may travel therewithin. Of course, movement of the second flange occurs when the tab of the first flange contacts an edge of the slot. Moreover, such linking means may be used between successive flanges or blades of any number to permit the same to rotate about a central pivot located above the aperture of the frame.
It may be apparent that a novel and useful fluid damper has hereinabove been described.
It is therefore an object of the present invention to provide a fluid damper which very accurately controls the flow of air in a ventilation system.
Another object of the present invention is to provide a fluid damper which is not susceptible to loss of a xe2x80x9csetxe2x80x9d due to the flow of fluid or air in a ventilation system.
Another object of the present invention is to provide a fluid damper which greatly eliminates noise associated with dampers of the prior art.
A further object of the present invention is to provide a fluid damper which exhibits great durability and may be used in air circulation systems having a high rate of flow.
Yet another object of the present invention is to provide a fluid damper system which is easily adaptable to clean room structures requiring precise control of airflow.
Another object of the present invention is to provide a fluid damper which very accurately controls the flow of fluid in a circulation system and is easy to manufacture, having a minimum of moving parts.
Yet another object of the present invention is to provide a fluid damper which greatly reduces the leakage of fluid through the damper when the damper is in its occluded configuration.
The invention possesses other objects and advantages especially as concerns particular characteristics and features thereof which will become apparent as the specification continues.